Dr. Sartor: It's a pleasure to be able to cover some of the critical updates in prostate cancer presented at the ESMO 2022 Conference in Paris. I'd like to start out by looking at a trial from a group called the STAMPEDE Group that many of you may be familiar with. The STAMPEDE Group has done a fantastic job of being able to look particularly at the metastatic hormone-sensitive prostate cancer space and to look at standard of care and a variety of new important trials that answer questions that people are asking about this disease.
So, what we have here, and this was presented by Gerhardt Attard out of London, is a very large series of trials all within STAMPEDE. So, first of all, there are about a 1000 patients who were randomized to androgen-deprivation therapy, plus or minus abiraterone. And, secondly, there's about 900 patients that were randomized between ADT plus or minus abiraterone and enzalutamide. And, by the way, when I say abiraterone, I really mean abiraterone and prednisone or prednisolone.
It turns out, in sort of typical English fashion, that the vast majority of these patients had de novo disease. About 94% of the patients had been diagnosed de novo at the beginning with metastatic disease. So, these were not patients who had had a radical prostatectomy and then recurred. We know now that the de novo metastatic has actually got a worse prognosis than does the recurrent disease, and that's based on studies from Chris Sweeney and colleagues. Now, just interestingly, they did allow the use of docetaxel but it was only in a minority of settings. So, what we really have is ADT plus or minus abiraterone, ADT plus or minus the abiraterone and enzalutamide.
The first thing I'm going to say, and this is an important conclusion, is there were no meaningful differences between the two arms, with an interaction term, the hazard ratio was 1.05. Basically, that means no difference in terms of the abiraterone or the abiraterone plus enzalutamide arm, and that was true for overall survival as well as a variety of secondary endpoints. So, adding enzalutamide to abiraterone did not add benefit. Now, it did add some potential toxicity, a little more hypertension, a little more liver function abnormalities. But I think the bottom line is that adding enzalutamide to the abiraterone does not add value above that of abiraterone alone. So, if you want to be treating patients with metastatic hormone-sensitive prostate cancer, then really best to use ADT, abiraterone, or as shown from other studies, ADT plus enzalutamide. But you really don't need the combination.
By the way, one of the things that was a little bit interesting, they had seven-year follow-up. Remember, these are de novo metastatic patients for the ADT and the abiraterone, and a great percentage of patients followed until death and they only lost about 5% of the patients. And what did they find? They found that the median survival was actually over five years, and at seven years, they ended up within about 48% of the people alive. So, I think that's a bit encouraging. There's a bit of nihilism at times about patients with advanced disease in presentation, but you can tell folks that they're going to be living for maybe more than six years when treated with ADT abiraterone, which is one of our standard therapies today. So that's the summary. That's what we learned from the STAMPEDE trial as presented by Gerhardt Attardat ESMO 2022.